Search for dissertations about: "linear stability"

Showing result 11 - 15 of 437 swedish dissertations containing the words linear stability.

  2. 11. On stability, transition and turbulence in three-dimensional boundary-layer flows

    Author : Seyed Mohammd Hosseini; Ardeshir Hanifi; Spencer Sherwin; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Receptivity; stability; optimal growth; three-dimensional bound- ary layers; crossflow instability; roughness control; freestream turbulence; sec- ondary instability; transition; turbulence;

    Abstract : A lot has changed since that day on December 17, 1903 when the Wright brothers made the first powered manned flight. Even though the concepts behind flying are unaltered, appearance of stat-of-the-art modern aircrafts has undergone a massive evolution. READ MORE

  4. 12. Ghosts and machines : regularized variational methods for interactive simulations of multibodies with dry frictional contacts

    Author : Claude Lacoursière; Bo Kåggström; Ander Klarbring; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Discrete mechanics; Variational method; Contact problems; Impacts; Least action principle; Saddle point problems; Lagrange Multipliers; Constrained systems; Multibody Systems; Numerical regularization; Constraint realization; Constraint stabilization; Dry friction; Differential Algebraic Equations; Nonsmooth problems; Linear Complementarity; Quaternion algebra; Numerical linear algebra; Physics modeling; Interactive simulation; Numerical stability; Rigid body dynamics; Dissipative systems; Computational physics; Beräkningsfysik;

    Abstract : A time-discrete formulation of the variational principle of mechanics is used to provide a consistent theoretical framework for the construction and analysis of low order integration methods. These are applied to mechanical systems subject to mixed constraints and dry frictional contacts and impacts---machines. READ MORE

  5. 13. Numerical simulation of the dynamics of a trapped molecular ion

    Author : Avazeh Hashemloo; Claude Dion; Michael Drewsen; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; diatomic molecular ion; linear Paul trap; rigid rotor; quantum rotational dynamics; wave-packet dynamics; time-dependent Schrödinger equation; stability;

    Abstract : This thesis explores the dynamics of a heteronuclear diatomic molecular ion, possessing a permanent electric dipole moment, µ, which is trapped in a linear Paul trap and can interact with an off-resonance laser field. To build our model we use the rigid-rotor approximation, where the dynamics of the molecular ion are limited to its translational and rotational motions of the center-of-mass. READ MORE

  6. 14. Extremum Seeking Control : Stability, Accuracy, and Applications

    Author : Khalid Atta; Ying Tan; Luleå tekniska universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Reglerteknik; Control Engineering;

    Abstract : In many applications, there is a variable that indicates the overall performance and that must be maximized, such as the output of a hydro power turbine or a mineral processing plant, or that must be minimized, such as CO2 emissions or the consumption of resources. Extremization of this variable (maximization or minimization) through adjusting the influencing manipulated variables is occasionally required without prior knowledge of the optimal values of the manipulated variables or of the optimized variable. READ MORE

  7. 15. Model Predictive Control in Flight Control Design : Stability and Reference Tracking

    Author : Daniel Simon; Johan Löfberg; Sébastien Gros; Linköpings universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Model Predictive Control;

    Abstract : Aircraft are dynamic systems that naturally contain a variety of constraints and nonlinearities such as, e.g., maximum permissible load factor, angle of attack and control surface deflections. READ MORE